battery_only houses aren't prioritizing self-consumption

[apigott]

At some points (ts = [17,18]) the battery_only houses sell electricity back to the grid directly from their battery. This conflicts with the Equation 20 which claims that the power discharged by the battery is consumed behind the meter.

P_{load}^{t-1} + P_{ch}^{t-1} - P_{dis}^{t-1} >= 0 (Eq. 20)

[apigott]

Equation 20 should be revised to the following, given that P_{dis} is restricted to be negative:

P_{load} + P_{ch} + P_{dis} >= 0 (NEW Eq. 20)

Rewritten to show that the magnitude of battery discharge is less than or equal to the load of all other systems:

P_{load} + P_{ch} >= |P_{dis}|, where |P_{dis}| = -P_{dis}

This can also be thought of as constraining P_{grid} to be positive which is anecdotally demonstrated in the revised optimal control strategy for Jason-INS3S

Note that the time index t vs t-1 is irrelevant.